If you were still entrenched in your old patterns, you probably wouldn’t open your self up to a new way of thinking of things, of engaging with life, and dealing with your fears.
The soul is what animates the physical body. When the soul pulls out of the body, the life force goes with it.
The fact is that some souls come in and don’t intend to stay for a long life time in the physical body.
I suggest you wait to mourn until at least 7 days after the death. Give the soul time to process it all. Just tell your self you will grieve after their soul has safely crossed over. This is their time, not yours. I do know this is easier said than done.
Sometimes we are not aware of our souls plan and we get stuck in a holding pattern.